Hi eric, so using that script I was able to identify 3 different areas that had openings.

2 of those areas were able to be sealed by making a planar surface from the 4 edges of the hole, and the third area was a kind of "L" shaped hole, so I drew in a line to separate the L into 2 sections, then one side was able to be sealed with a plane and the other seemed to be not quite planar so I used Network there instead.

I've attached the result model which is now a solid.

I'll take a look at your fillet problem next.

- Michael